what type of rotor should I get if I buy a brembo caliper

 

Nearly every manufacturer makes rotors for the brembo's, just check the specifications to make sure it's the right one. The answer to your questions depends on a GREAT MANY details, none of which were provided. Is this a track car? How hard do you drive your vehicle? What exactly are your needs. Most people just go with something fairly basic but still has enough internal vanes to resist warping.

 

I got these brembo braker for the front. I would like to know the size of the rotor ( Infiniti G35 2006 )

 

Buy rotors for a brembo equippped 2003-2004.

 

Rotorsbrembo equippped 2003-2004. ( it does not matter if my G35 is from 2006 ) should be Rotors 324x30

 

The brakes were all interchangeable so no it doesn't matter but you will need the brembo brake lines also I believe. That rotor diameter sounds about right but every manufacturer will specify BREMBO EQUIPPED as the vehicle option. 2003-2004 there were two options for brakes you either had Brembo's or you didn't. 2005-2007 there was only a single option.

Use google to search for this, there's hundreds of threads on the subject.

 

I already have all the lines and everything I just need the rotors and I do not want to be wrong

 

You've been given clear direction on where and what to look for. Follow cleric's advice and you'll be money.